ABSTRACT
The generation of antitumour immunity depends on the nature of dendritic cell (DC)-tumour interactions. These have been studied mostly by using in vitro-derived DC which may not reflect the natural biology of DC in vivo. In breast cancer, only one report has compared blood DC at different stages and no longitudinal evaluation has been performed. Here we conducted three cross-sectional and one one-year longitudinal assessments of blood DC in patients with early (stage I/II, n=137) and advanced (stage IV, n=36) disease compared to healthy controls (n=66). Patients with advanced disease exhibit markedly reduced blood DC counts at diagnosis. Patients with early disease show minimally reduced counts at diagnosis but a prolonged period (1 year) of marked DC suppression after tumour resection. While differing in frequency, DC from both patients with early and advanced disease exhibit reduced expression of CD86 and HLA-DR and decreased immunostimulatory capacities. Finally, by comparing a range of clinically available maturation stimuli, we demonstrate that conditioning with soluble CD40L induces the highest level of maturation and improved T-cell priming. We conclude that although circulating DC are compromised by loco-regional and systemic breast cancer, they respond vigorously to ex vivo conditioning, thus enhancing their immunostimulatory capacity and potential for immunotherapy.
Subject(s)
Adenocarcinoma/blood , Apoptosis , Breast Neoplasms/blood , Dendritic Cells/immunology , Neoplasm Recurrence, Local/blood , Adenocarcinoma/pathology , Adult , Aged , Aged, 80 and over , Blood Cells , Breast Neoplasms/pathology , CD40 Ligand/physiology , Case-Control Studies , Cell Count , Cross-Sectional Studies , Culture Media, Conditioned , Female , Flow Cytometry , Humans , Immunophenotyping , Middle Aged , Neoplasm Recurrence, Local/pathology , Neoplasm Staging , PhenotypeABSTRACT
Dendritic cells (DC) from distinct DC subsets are essential contributors to normal human immune responses. Despite this, reliable assays that enable DC to be counted precisely have been slow to evolve. We have now developed a new single-platform flow cytometric assay based on TruCOUNT beads and the whole blood "Lyse/No-Wash" protocol that allows precise counting of the CD14(-) blood DC subsets: CD11c(+)CD16(-) DC, CD11c(+)CD16(+) DC, CD123(hi) DC, CD1c(+) DC and BDCA-3(+) DC. This assay requires 50 microl of whole blood; does not rely on a hematology blood analyser for the absolute DC counts; allows DC counting in EDTA samples 24 h after collection; and is suitable for cord blood and peripheral blood. The data is highly reproducible with intra-assay and inter-assay coefficients of variation less than 3% and 11%, respectively. This assay does not produce the DC-T lymphocyte conjugates that result in DC counting abnormalities in conventional gradient-density separation procedures. Using the TruCOUNT assay, we established that absolute blood DC counts reduce with age in healthy individuals. In preliminary studies, we found a significantly lower absolute blood CD11c(+)CD16(+) DC count in stage III/IV versus stage I/II breast carcinoma patients and a lower absolute blood CD123(hi) DC count in multiple myeloma patients, compared to age-matched controls. These data indicate that scientific progress in DC counting technology will lead to the global standardization of DC counting and allow clinically meaningful data to be obtained.
Subject(s)
Dendritic Cells/immunology , Flow Cytometry/methods , Adult , Aged , Blood Cell Count/methods , Breast Neoplasms/blood , Centrifugation, Density Gradient , Dendritic Cells/cytology , Female , Humans , Immunophenotyping , Male , Microspheres , Middle Aged , Multiple Myeloma/blood , Reproducibility of ResultsABSTRACT
Tradicionalmente, la vitamina D ha sido reconocida como una hormona de acción endocrina que se ha relacionado con la homeostasis del calcio. Estudios realizados durante los últimos 10 años, han permitido ampliar este concepto. El calcitrol, la forma más activa de la vitamina D es una molécula que ejerce amplios efectos a través de mecanismos genómicos mediados por el VDR, (Vitamin D Receptor, un receptor perteneciente a la familia de los receptores de hormonas esteroideas - tiroideas) y mecanismos no genómicos mediante la regulación de los niveles de calcio intracelular. A la luz de estos hallazgos, el calcitrol aparece ahora como un modulador de la respuesta inmune y un factor hormonal con efectos antiproliferativos y prodiferenciadores en diversas lineas tumorales, un hallazgo prometedor. Sin embargo, el efecto antineoplásico observado en modelos in vitiv, se ha visto opacado en gran medida por el efecto hipercalcémico de la hormona in vivo, haciendo de su aplicación clínica, una meta difícil. Por este motivo, el desarrollo de moléculas análogas pero con un efecto hipercalcémico disminuido, que puedan constituirse en alternativas de tratamiento el manejo de desordenes en hiperproliferativos como la psoriasis y varios tipos de cáncer, constituye un avance novedoso con importantes repercusiones para la practica medica